Hydrogen generator

Abstract

A plurality of catalysts are arranged in a desirable order based on the temperature gradient existing in the reaction chamber. The operating temperature of the catalyst and the temperature of the portion of the reaction chamber it is in, are matched so as to avoid catalytic degradation and/or catalytic inactivity.

What is claimed is: 
     
       1. In a hydrogen generator for producing a hydrogen rich gaseous mixture by endothermic catalytic conversion of alcohol or aqueous solution thereof, including a conduit through which hot gases flow in one longitudinal direction, and a catalyst-containing reaction chamber extending axially along said conduit to be in heat-exchanging relationship therewith, the improvement comprising said reaction chamber having formed therein upstream and downstream sections which are successively arranged with respect to the flow of the heated gases, said upstream section communicating with an inlet through which said alcohol or aqueous solution thereof is supplied to said reaction chamber, said downstream section communicating with an outlet through which converted gaseous mixture is delivered from said reaction chamber, and first and second catalysts having different operating temperature ranges, said first catalyst having a higher operating temperature range than said second catalyst and being disposed in the upstream section, and said second catalyst being disposed in the downstream section thereby providing for optimum conversion as the hot gases give up heat to the endothermic reaction and lower in temperature as they pass through said conduit. 
     
     
       2. In a hydrogen generator used with an internal combustion engine for supplying thereto a hydrogen rich gaseous mixture by endothermic catalytic conversion of alcohol or aqueous solution thereof, including a conduit through which the hot exhaust gases flow in one longitudinal direction, and a catalyst-containing reaction chamber extending axially along said conduit to be in heat-exchanging relationship therewith, the improvement comprising said reaction chamber having formed therein upstream and downstream sections which are successively arranged with respect to the flow of the exhaust gases, said upstream section communicating with an inlet through which said alcohol or aqueous solution is supplied to said reaction chamber, said downstream section communicating with an outlet through which converted gaseous mixture is delivered from said reaction chamber, and first and second catalysts having different operating temperature ranges, said first catalyst having a higher operating temperature range then said second catalyst and being disposed in the upstream section, said second catalyst being disposed in the downstream section, in which said first catalyst is a platinum catalyst and said second catalyst is zinc oxide-chromium oxide catalyst, and in which said inlet is connected to a conduit which communicates with a source of alcohol or aqueous solution thereof and has a waved portion disposed in the exhaust gas stream thereby providing for optimum conversion as the hot gases give up heat to the endothermic reaction and lower in temperature as they pass through said conduit. 
     
     
       3. In a hydrogen generator used with an internal combustion engine for supplying thereto a hydrogen rich gaseous mixture produced by endothermic catalytic conversion of alcohol or aqueous solution thereof, including a conduit through which the hot exhaust gases flow in one longitudinal direction, and a catalyst-containing reaction chamber extending axially along said conduit to be in heat-exchanging relationship therewith, the improvement comprising said reaction chamber having formed therein upstream and downstream sections which are successively arranged with respect to the flow of the exhaust gases, said upstream section communicating with an inlet through which said alcohol or aqueous solution is supplied to said reaction chamber, said downstream section communicating with an outlet through which converted gaseous mixture is delivered from said reaction chamber, and first and second catalysts having different operating temperature ranges, said first catalyst having a higher operating temperature range than said second catalyst and being disposed in the upstream section, said second catalyst being disposed in the downstream section, in which said first catalyst is zinc oxide-chromium oxide catalyst and said second catalyst is zinc oxide-copper oxide catalyst, and in which said inlet is connected to a conduit which communicates with a source of alcohol or aqueous solution thereof and has a waved portion disposed in the exhaust gas stream thereby providing for optimum conversion as the hot gases give up heat to the endothermic reaction and lower in temperature as they pass through said conduit.